Confirmation holism, also called epistemological holism, is attributed to Willard van Orman Quine's extension of Pierre Duhem's problem of underdetermination as to physical theory, Quine's extension of underdetermination to all knowledge claims, since no theory of any type can be tested in isolation, but only embedded on a background of innumerable and often undetermined factors. (See Quine-Duhem thesis.) Confirmation holism thus involves the problem of credit assignment, determining which aspect of the overall network to attribute a theory's failure to[clarification needed]. And by ontological relativity, explicated by Quine, one can always protect one's explanation of phenomena by attributing failure to some aspect outside the explanation.
Underdetermination in physical theory
By 1845 astronomers found that the orbit of planet Uranus around the Sun departed from expectations. Not concluding that Newton's law of universal gravitation was flawed, however, astronomers John Couch Adams as well as Urbain Le Verrier independently predicted a new planet, calculated its weight and orbit through Newton's theory, and so was discovered the planet Neptune where predicted. And yet neither did this empirical success of Newton's theory verify Newton's theory.
Le Verrier soon reported that Mercury's perihelion—the peak of its orbital ellipse nearest to the Sun—advanced each time Mercury completed an orbit, a phenomenon not predicted by Newton's theory, which astrophysicists were so confident in that they predicted a new planet, named Vulcan, which a number of astronomers subsequently claimed to have seen. In 1905, however, Einstein's special theory of relativity claimed that space and time are both relative, refuting the very framework of Newton's theory that claimed that space and time were both absolute.
In 1915, Einstein's general theory of relativity newly explained gravitation while precisely predicting Mercury's orbit. In 1919, astrophysicist Arthur Eddington led an expedition to test Einstein's prediction of the Sun's mass reshaping spacetime in its vicinity. The Royal Society announced confirmation—accepted by physicists as the fall of Newton's theory. Yet few theoretical physicists believe general relativity a fundamentally accurate description of gravitation, and instead seek a theory of quantum gravity.
- Curd, Martin; Cover, J.A. (Eds.) (1998). Philosophy of Science, Section 3, The Duhem-Quine Thesis and Underdetermination, W.W. Norton & Company.
- Duhem, Pierre. The Aim and Structure of Physical Theory. Princeton, New Jersey, Princeton University Press, 1954.
- W. V. Quine. 'Two Dogmas of Empiricism.' The Philosophical Review, 60 (1951), pp. 20–43. online text
- W. V. Quine. Word and Object. Cambridge, Mass., MIT Press, 1960.
- W. V. Quine. 'Ontological Relativity.' In Ontological Relativity and Other Essays, New York, Columbia University Press, 1969, pp. 26–68.
- D. Davidson. 'On the Very Idea of Conceptual Scheme.' Proceedings of the American Philosophical Association, 17 (1973-74), pp. 5–20.
Theories of truth